I have a bltouch clone which work fine on glass bed. After switching to textured PEI sheet, it’s variance trippled to 0.1mm, which make my bed mesh all wobbly.

I’m I suppose to remove the steel plate when making the bed mesh? Do you home Z with a probe with this setup?

The weirdest thing is, despite all this all my prints adhere completely fine. I guess PEI is just that good.

  • ffheinEnglish
    3•1 year ago

    Does the variance return to normal if you switch back to the glass plate? If you probe multiple times on the same spot, do you still get large variance?

      • ffheinEnglish
        2•1 year ago

        If you press down on the PEI/steel sheet manually, does it look like it’s flexing or does it feel stable? When you switched from glass to steel+PEI, did you put an adhesive magnet sheet on the print carriage, or are you using some other method to hold the print surface in place? Just found a post on reddit where someone discovered that their build plate only sticks to the magnetic sheet when they rotate the plate 90 degrees, so perhaps that’s worth a try.

        • @x7tYnC6cOPEnglish
          1•1 year ago

          Nah it rock solid. The variance come from the texture itself.

          • ffheinEnglish
            1•1 year ago

            Not doubting you, but I can’t think of a logical reason for why it would be like that. The probe pin shouldn’t push down hard enough to be able to deform the PEI

            Perhaps as a workaround you could configure the firmware to probe each spot 3 times and average the result, if you don’t mind the extra time levelling would take?

            • @x7tYnC6cOPEnglish
              1•1 year ago

              I meant the probe is deflected by the texture. Taking multiple sample is what I’m doing, yes. It take at least 5 samples for it to be reasonably smooth, which is why I’m asking other experience.

              • ffheinEnglish
                1•1 year ago

                You mean you think the probe slides off the bumps in the texture? I think the probe should be stiff and light enough to not do that, but perhaps you could’ve been unlucky if it’s a clone not from a well known brand (e.g. Trianglelabs… even Creality’s probe’s are supposed to be quite good afaik)

                • @x7tYnC6cOPEnglish
                  1•1 year ago

                  Yes. I’m certain it is a build quality problem. The probe is just plastic and by design hang freely. Even a steel rod with bearing can easily be deflected by a few tens of micron.